It is proposed to extend Incentive Theory to account for long-term behavioral contrast and extinction, and to clarify the role of attention in the organism's allocation of behavior to competing activities. The various effects of training regimens on resistance to extinction will be reviewed, and quantitative theory that will account for phenomena such as the partial reinforcement extinction effect, the overtraining extinction effect, and the effects of interpolated schedules of reinforcement will be derived. In all cases the magnitude of the incentives involved and the species of organism studied are likely to play a critical role, and a theoretical explanation of why that is the case will be suggested. The fundamental mechanisms in incentive theory that will be developed are the accumulation of arousal to signals of reinforcement, and the renormalization of that arousal based on the animal's internal clock, whose speed is adjusted on the basis of overall frequency and value of incentives in real time. The same mechanisms should help us to understand both incentive and behavioral contrast, although they are unlikely to be able to account for the types of contrast that are manifest early in training. Notions of behavioral competition, perceptual contrast, and adventitious reinforcement will be evaluated for those effects. The theory invokes attentional processes in its predictions of the acquisition of autoshaping and in selection of alternate patches; current theories of association learning will be studied for their usefulness in extending Incentive Theory; conversely, the theory may shed light on empirical data by generalizing our notions of the maximum associative strength of stimuli to include intertrial interval and scheduling parameters as determinants of that maximum. Incentive Theory provides a very different approach to learning than traditional reinforcement theory, and thus should inform alternate conceptualizations of training programs for regular and special populations, as well as form a theoretical basis for our understanding of the tuning of the organism to the rhythmicity of its environment, either to its benefit or its detriment.